Reversing apparatus for regenerative furnaces.



' T. s. BLAIRJB, REVERSING APPARATUS FOR REGEN BBATIVEFURNAOES.

' 929,277. Patented Ju1y27,1909. BBHEET BE'EBT- 1.

. Tl Sn J31 I BEVBBSING APPARATUB FOB BBGENEBATIVE FURNACES. v

- TILED, IAB. 16, 1909 i h flow flZawJ);

:r. s. BLAIR, J3. BEVERSING APPARATU8 FOB REGBNEBATIVE FURNACES.

APPLICATION FILED UAR. 18, 1909. Patented 27' 8 SHEETE SHEET '5.

-v [rel/672251 T. s. BLAIR, JR. REVERSING APPARATUS FOR BEGENEBATIVE FURNACES.

APPLIOAIION FILED HABJB, 1909. 929,277. Patented July 27, 1909.

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s. BLAIR, JR. BEVEBSING APPARATUS FOR BEGENEBATIVE FURNACES.

- APBLIOATIOH FILED MAR. 16, 1909. I 929,277, Patented July 27, 1909.

8 SHEETS-SHEET 7.

T. S. BLAIR, In.

BBVEBSING APPARATUS FOR BEGENERATIVE FURNACES. APPLICATIOI FILED MAR. 16, 1909.

= Patented July 27, 1909. 88HEBTB-BHEBT 8.

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YORK.

UNITED STATE-SgF T, DEERE;

vfjUlEIOllLIASS. BLAIR, JR., OF ELM'HUR.ST, '-ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

BLAIR ENGINEERING COMPANY, OF CHICAGO, ILLINOIS,

A CORPORATION OF NEW REVERSING"APPARATUS FOR REGENERATIVE FURNACES.

Patented July 27, 1909.

To all whom it may conccm:

:Be'it known that I, THOMAS S. BLAIR, Jr., a citizen of the United States, residing at El'mhurst, in the county of Dupage and State of Illinois, have invented a new and useful Improvement in Reversing Apparatus for Regenerative Furnaces, of which the following is a specification.

I My invention relates to an improvement in the" equipment which forms a necessary feature of the regenerative type of furnace for'reversing the-course through it of the burning gaseous fuel. In all such equipments hithertoprovided, a so-called valve for directing the gases to and from the furnace under the force of the stack-draft is provided as a self-contained structure with internal longitudinal partition-walls, usually offire-brick, forming the tines and affording the only separating mediumbetweenthem. This structure is surmounted by a metal platform having openings through it for terminals of the 'flu'es and on which is supported mechanism for switching'the course through the furnace of the gas and air. It is to the construction thus generally outlined that nuch'of the trouble and expense involved in operating a furnace of the type "referred'to is attributable, since both the hot gases in their course to the. furnace and the hot products of combustion in their course to the stack from the furnace pass through the same fine-containing structure or valve, so that the'mere wall-s separating the flueteriuinals therein from each other, being subjected to the, intense heat of the gases, and to difierences in the temperature of those coursing along opposite sides of the same wall, tend, especially under the very forcible suction-action of the stack-draft, to-

crack and sag and thus cause leakage through them from the gas-flue to the draftflue. When such leakage occurs the necessarily seeks the more direct outlet, thereby atlorded, to the stack, rather than the more roundabout course by' way of the furnace and its regenerative chambers and fines to the opposite side of the partition, with the inevitable result ofrapidly impairing the structure to an extent which incurs not only a great waste of fuel, by its detlectipn to the stack, but such inefficient operation of the furnace, because of both an inadequate supply thereto of gas and diu'iinished draft, as to render repairs imperativcly necessary.

Moreover, the platform referred to and mechanism upon it, being wholly or partly of metal and under constant subjection to the intense temperature-conditions, angdavariations therein, of the gas; sulfer s rely from deterioration under such exposure,"besides inducing leakage underneath the platform, by warping thereof, from the gasfiue into the draft-flue. The-seriousness of the frequently-occurring requirement for re pairs, made necessary by the faulty construction thus explained, may be appreciated in considering the fact that to, enable them' to be-made the gas-supply must be entirel .cut OH and the furnace, therefore, shut'. own, and that, inasmuch as the valve structureis at a high temperature and the bric'k' flue:

terminals are underground and consequently diflicult of access, the-work.of, repair1ng1s extremely arduous and very slow besides .being excessively expensive; ,Furth'ermore, while the gas is shut ofi' thefurnacevis out of commission incurring. consequentgloss in production, and the loss of it'sheatnece'ssitates an extravagant expenditure for fuel to restore it to operation. NVhile the tendency to leakage from gas-flue to draft-flue, which is greatest at the reversing-point because of the enormously-excessive draft there over that around through the furnace, the difficulty ofmaking repairs, with consequent loss in production, and the waste of fuel, all hereinbefore referred to, are faults inherent in every known construction of furnace-reversing equipment; they -are especially marked where the parts of the reversing mechanism are housed and Operated within a gas-box, since the latter augments the difficulty of making repairs in the housed mechanismfas also that of detecting any leak therein in its incipiency, so that such leaks are rarely discovered until they have become so bad as to seriously impair the operation of the furnace and work great damage to the mechanism, rendering necessary imfnediate and extensive repairs. All thefaults, thus explained are overcome and other advantages are obtained by my improvement hereinafter described and illustrated in the accompanying drawings.

' A primary purpose of the present invention is to provide a valveless reversing apparatus for a reverberatory regenerative furnace, meaning thereby one that entirely dispenses with the so-called valve. in prior ap- .paratus for the same purpose, one known form'of which is a rotatable plate carrying the adjustable connecting elbows or ducts through the medium of which the reversing action is accomplished. These valves are objectionable in being cumbersome and as essentially involving a structure of the apparatus whereby leakage is caused between the ends of the upright flue-terminals and those of the swinging ducts; and by omitting any valve as a part of my construction of a reversing apparatus I avoid the serious objection referred to and am enabled to utilize advantage a regulating valve in the gas ;ipply flue, an independent and more satisfactory means for controlling the supply of gas and entirely cutting it off during the period of each reversal of the furnace.

The construction of the uptake (and downtake) flue-terminals whereby they are entirely inde' endent of each other, and without anyform of inter-connection from one to the other except that afforded by the ducts, constitutes the more important feature of my improvement which is intendedto be characterized in the appended claims wherein the flue-terminals are described, as

being disconnected at their ends.

Referring to the drawingsFigure 1 shows my improved reversing apparatus by a perspective view looking from the adja cent furnace toward the stack and illustrating the parts in one operating position.

Fig. l is a similar view of the same showing the switching ducts intermediate their two operative positions and undergoing transfer to the position opposite that illustrated in Fig. 1, this last-named position of the same being presented, by a similar View, in Fig. 1". Fig. 2 is a diagrammatic-plan view of the apparatus showing its; operative relation to the furnace-fines and stack between which it is interposed. Fig. 3 is another diagram showing the connections between the pivotal ends of the switchin ducts for turning themall simultaneous y by turning one. plan view of the annular seat provided on the terminal of'the air-flue, which leads to the stack, for the pivotal switching-dudt whichconnects the air-flue terminals with the stack. Fig. 5 is a section on line 5, Fig.

4, and Fig. 6 is a section on line 6, Fig. 4.-

Fig.7 is an enlarged plan view of one of the two similar air-flue terminals equipped with a cap-valve for controlling the airsup ly, and Fig. 8 is a section on line 8, Fig. 7 Fig. 9 is a section like that presented in Fig. 4 but through one of the two similar annular seats for the pivotal switching-ducts which control the flow of the gaseous fuel through the furnace and direct the discharge of the products of combustion to the stack. Fig. 10 shows a cross-section through one of the similar annular water-sealed llue-tcrmi- Fig. 4 is an enlargednals for -receiving the free ends of the switching-ducts; and Fig. 11 is an enlarged section on line '11, Fig. 2, showing the construction of one of the two similarvalved passages for controlling the supply of the gaseous fuel from the. source thereof (as gasproducer or place of storage) tothe furnace through the reversing apparatus.

The desirable location for the reversing apparatus is that represented, being at acentiaint toone side of the furnace, indicate atF, (Fig. '2), between the latter and Ur, and within the confines of an open framework E, which rises fromthat level to a height adapting it to form a sect on of the the; stack S on the ground-level, indicated at i usual elevated working platform ofthe fur-- nace. The flue 12 (Fig. 2), which leads underground into the base of the stack, has its outer end forming a vertical terminal 13 at the center of the base of the structure P. The

hues indicated at 14 and 15for directing,

alternately, the fuel as through the furnace and the products 0 and the flues indicated at 16 and 17 for directing, alternately, combustion -promotiug air through the furnace to the stack, are each built as a separate independent structure of suitable material (preferably firebrick), and they are spacedapart to enable them to bethoroughly insulated from each other either by the air-spaces between them or, when they are, more properly, built underground, by a filling in the s aces between them of earth, concrete or the like heat-insulating material. The-showing in Fig. 2 of the way combustion from the discharge-end of the furnace to the stack,

these four flues run is intended to. be merely indicative, since their relative arrangement may be varied fordiflerent furnaces in equipping them with my" improvement. However, they all lead to a common point by ending in the reversing apparatus in vertical terminals at 14, 15, 16 and 17, re-

spectively, shown as clustering about the central stack-flue terminal 13. A vertical branch 18 of the flue 12 leads into the latter and forms a second terminal thereof in advance of the terminal 13 for the purpose hereinafter explained; but this branch may, obviously, form the terminal of a separate flue leading to the stack. I

The gas used as fuel goes from the source of supply to the furnace through a pipe 19 discharging into another pipe 20 which extends transversely thereto (Fig. '2), and opens at its ends into similar valve-chambers 21 and 22, ear like that'shown, as a preferred construction, in Fig. 11; these chambers being located adjacent to the stack for connection, respectively, with-the flue-ter1ni-. nals 14 and 15. Each valve-chamber is verticnlwell- 24 in'the open base of which is provided a. seat 25 for a valve26, shown of ordinary mushroom variety with its stem I from a. header 47 through branches leading 27 working through a stuiiing-box 28 in the well'cover 29. This valve controls the flow of the gas from the well-section to the outlet-passage 30. At the base of the inletpassage 2 is a ate-closed opening 31 leading to a vertical pit 32 open at its top and through which to gain access to the valvechamber for cleaning it, repairing the valve, and the like.

(3n the flue-terminal13is rotatably mounted one end of a switching-duct 33 shown in its preferred form of an arc-shaped tube and which is best formed of steel plate lined with fire-brick. The means I prefer to employ for rotatably mounting this duct are,

shown in Figs. 4, 5 and 6, to cotiperate with an annular'wa-terrseal trough 34 capping the flue-terminal 13 and provided with an overflow-chamber 35, at a suitable point on its circumference and partitioned by a screen 36 from the trough at its discharge-opening 37 therein. The outer wall of the trough forms a track 38 for wheels 39, of which four are shown to be employed, journaled at equal intervals apart in a ring 40 encircling an annular reinforcing thimble 41. surroundingan-d seating the adjacent end of the tube 13 and which dips into the trough 34; and the ring 40 yieldingly supports the tube by trunnions 42 projecting at diametallyopposite points of' the thimble and r journaled in bearings 43 on the ring. The outer circumference of the ring has formed 2 it three cable-grooves 44, for the purpose in reinaftei plained.

switching-duct- 45, exactly like the duct but of smaller dimensions, is rotatably and ti iingly mounted at. one end on the flueterininal 14 in the same way as that described of mounting the duct- 33; and the parts are denoted by the reference-characters for the ring, 39 for the wheels, and 41 for the thimble which dips into the annular trough marked 34 and forming the track 3S 9) and the ring contains a cable groove 4-4 in its periphery.

switchlug-duct 4G, in all res 'iectslikc the leach of the tlucdr minals 16 and 17 as also those of the .alve outlet-passages 20 and that to "netld'iy th outer end of the 1S, equipped with water-seal ran in i s. H, and 10 and similar .azt the pivotal ends of the switching-ducts, involving an annular trough 34 into which dips a thimble 41' encircling the free end of the duct. ater may be supplied to the several troughs for sealing the joints between the parts meeting in them in any suitable manner to discharge through their overflows to any desired point. in Fig. 3 the sealing water is shown to be supplied to that 15, is rotatably and tiltingly mounted l therefrom to the different troughs.

With the switching-ducts in the relative positions presented by fulllines in the diagram (Fig. 2), which corresponds with the showing in Fig. 1, the duct connects the gas-flue terminal 14 with the terminal of the adjacent gas-valve device 21, the other, 22, being closed; the duct 46 connects the gas-flue terminal 15 with the flue 12 at its branch 18, and the duct 33 connects the stack-flue terminal 13 with the air-flue 17 at its terminal 17. The course of the gas is then by way of the' duct 45 and fine 14 through the furnace whence part of the products of combustion discharge through the fine 15, duct 15 and fine 12 to the stack; and the airis sucked by the stack-draft through the terminal 16 flue 16 and furnace, whence the rest of the products of combustion discharges to the stack by way of the fine 17, duct and flue 12. To reverse the course of the gases, the valve 21 is closed to shut ed the gas-supply through it, and the switching ducts, after disengaging their swinging-ends from the respective waterseals, are turned on their pivotal ends, all as hereinafter described, to the positions represented by dotted lines, wherein the duct 45 registers with the branch 18, theduct 46 with the valve 22 at 30, and the duct 33 with the terminal 16 whereupon the valve 22 is opened to cause the gas-supply to course by way of the duct 46, terminal 15 and flue 15 through the furnace, and the air courses through the furnace from the terminal 1'?" by way of the flue 17; the products of conithe stack by way of the fines 14 and 16, ducts 45 and 33 and flue- 12. Preparatory to swinging the switching-ducts from either position to the other, their free ends must be raised to clear the water-seal troughs; and it is desirable that the ducts shall be swung simultaneously by one operation. These functions may be performed by any suitable mechan ism adapted to be operated by hand or, and preferably, by power. As suitable means for so swinging the ducts, I provide'the cable connections shown in Fig. 3, though chains or gears may be substituted for them. A cable 48 passes about qne groove 44 in the ring 40 on the duct 33 and about the grooved ring 44' on the journaled end of the duct 45,

jacent stem .51 of a piston contained in a cylinder 52 and adapted tobe actuated by hydraulic or other pressure. For raising the free ends of the three ducts simultaneously operation of all from a single point to cause the action by the cylinder 53 of simultaneously' raising the ducts to be followed by that of a cylinder 52 .of-turning them to register properly in their reversing positions,

where they dro to their respective watersealed seats by s acking the saidcables. The hand-Wheels 57 on stems 58 workingin bearings 59 on the frame P and having pulley- .guided connections 60 with the gas-valve stems 27 form suitable means for adjustingthe valves 26 relative to their seats.

The air-supply through the terminals 16* I and 17 shouldbe regulable to .suit conditions in the furnace-,-requiring the admission of more or less air. For this purpose I provide each of these terminals with a cap-valve 61 (Figs. 8 and 9) hingedly supported-on suitable bearings 62 extending from the outer wall of the respective trough 34", witha crank-arm 63 extending from one end 'of the hinge-pintle 64 and terminating in a loop 65. A divided rod 66 pivotally connected at its inner ends, as at 67, with the J duct 33 extends at its outer ends through the loops of the two arms 63, adjacentto each of which the rod is provided with 'a trans verse hole 68 for a pin v or stop 69. Each cap-valve is connected by a cable 70, passing over pulleys suitably located on the frame P,

with a different adjusting device 7 1, like.

that hereinbefore described as comprising the'parts 57, 58 and 59, to enable the cap- -valves to be set and held at any position relative to 'the air-inlet flue-terminal) on which it is provided, for rendering the lat- -ter more or less open to the ingress of air.

In each of Figs. 1 and 1 the cap-valve cov'- ering the openair-inlet terminal is shown to be set to assume relative thereto an angle of about 20 degrees. \Vhen the switchingducts have been raised by the device 53 preparatory to swinging them from either posi-' tion to the other by operating the-proper device 52, they will, on attaining such position, be dropped into place through the medium ofthe device 53. In swinging from one'position to the other, as indicated in Fig. 1, the duct 33 carries the rod 66 in the direction to permit the cap-valve on the terminal 17 to lower by gravity as far as its setting will permit, but the other cap-valve is not raised, to make way for seating the free end of the duct 33, until the adjacent pin 69en- 'counters the respective crank-arm 63 in pass ing through the loop 65, whereuponthe ralsing of that cap-valve begins. As thus be seen, therefore, by providing for lost motion in the movements of the rod 66 until thereon, encounters the crank-arm in its path, the setting of the cap-valve in use need not be disturbed until just previous to mak- 8D- ing the stack-connection therewith, while they other cap-valve will automatically assume its set position practically as soon as its airsupply controlling function is required to be brought into play.

As will be apparent from the foregoing description, the operation of my improved reversmg mechanism may be likened to that of a switch in a railroad-track, each switch:

ing-duct being seated at one end to rotate f about a central axis for swinging its op- -posite free end. It will also be noted that my improved mechanism is devoid of any valve in the sense of "the valve-device re; quired to be employed in all other furnace; reversing apparatus known to me, and

which is' usually in the form of a rotary circular plate carryingtubular flue-connecting elbows and serving to cut off the stack and gas flue-terminals by turningthe valve to produce the furnace-reversal. There is; therefore, in my device, no valve nor valveseat in contact with the hot products of combustion to obstruct their flow and to become warped and 'leak,,or to -gather deposits of soot or hard carbon, causingleaks.

When-any repair isrequlred as-the result,

say, of accident tothe mechanism of my improved device, theg'as or air switching-duct is so adjusted as'tobe'come a part 0 the draft-system from the outgoing end o the furnace. If the repairais required on a 'gas- I duct or on any part of its mechanism, that duct is disconnected from the respective flue terminal, thereby breaking "the-'i'connection through the flue of'tl'iat' terminal to the stack, which has the same effect as introducing a damper into the flue; and the draft thenall passes through the air-duct 33 to the stack, the furnace continuing in normal operation. Should the repair be required on the duct 33, itis disconnected from either terminal 16 or I 17 as the case may be, thereby causing the products of combustion from the furnace all to pass through the gas-flue to the stack.

All parts of the mechanismbeing exposed and always cool andaccessible, parts may be repaired or replaced at any time, and this without even requiring the gas to be shut off from the furnace, thereby redaicing the. cost of maintenance to the minimum andsav ng;

15, a pin 69, in any position of adjustment forth.

any loss or extravagant use of the gas, the flow of which, moreover, to the furnace, as

' also the draft to the stack, are rendered by my improvementfree, being unobstructed by short turns, since the full openings through the fines are effective, thus materially increasing the draft on the furnace. Furthermore, the flue-construction not only prevents the possibility of any leak between flues from one to another, but the construction of the reversing mechanism renders it equally proof against leakage, from either gas or air passage to the stack, or between gas and air passages, however long the apparatus mayhave been in operation.

hat- I claim as new and desire to secure by Letters Patent is I L'In combmat1on,'a furnace of the 'character described provided with a stack, a set of air and gas fiues for each end of the furnace communicating through the furnace with the stack, the uptake flue-terminals presented adjhcent to the furnace being separate structures insulated from each other and disconnected at their ends which project above the ground-levehand reversing mechanism for the furnace coiiperating with the fiues at said terminals, for the purpose set acter described provided with a stack, a set.

of air and gas fines for' each end of the furnace communicating through the furnace. with the stack and presenting terminals adjacent to the furnace, regulating-valves in the gas-fines and valveless reversing mechanism for the; furnace coiiperati-ngwith the fines atsaid terminals, for the purpose set forth. I v

4. In combination, a furnace of the character described provided with a stack, a set of air and gas fines for each end of the furnace communicating through the furnace with the stack and' presenting terminals adjacent to the furnace, and valveless reversing mechanism for the fuinace regulating valves in the gas-fiues ad uStabIy supported lmmediately on said terminals to cooperate thereat with the fiues, for the purpose set forth.

5. In combination, a furnace of the character described provided with a stack, a set of air and --gas.flues for each end of the furnace communicating through the furnace with the stack and presentingterminals, reg ulating-valves in the gas-fines a flue leading to the stack and presenting terminals, gassupply passages presenting terminals, and

switching ducts, rotatably mountedrat one stack-flue terminals and adaptedto be swung thereon tore ister their free ends respec- .end on said gas-flue terminals and on said,

tively with eit ier air-flue terminal, either of said passage-terminals and the other stackfiue terminal, for the purpose set forth.

(3. 111a reversing ap aratus. ofia regenerative furnace, the coin inationwith a flueterm ma], of an annular water-trough thereon l forming of itsouter flange a circular track,

a switching-duct provided on end with a I 'rmgcarrymg wheels riding on said track in rot'ating said duct, andwith means coiiperating with said trough to forma waterseal j omt, and flue-terminals with which the opposite end of said ductis registrable' by turning it on its support, for the purpose set forth. I i

7. In a'reversing apparatus of a regenerative furnace, the combination, with a flueterminal, ofv an annular water-trough th ere on forming of its outer flange acirfcular track, a switching-duct provided on one end with a ring carrying wheels riding on ,said track in rotat ng said duct, and. with means coiiperating with said trough to form a.

water-seal joint, flue-terminals with which the opposite end of said duct is registrable by turning iton its support, and means on said opposite end of the duct and on each of said flue-terminals cotiperating to form a water-seal joint, for the purpose setforth.

8. In a reversing apparatus of a regenerative furnace, a switching-duct rotatablyand tiltingly mounted at one end onone fineterminal of the furnace to adapt it -to be swung on said terminal to register its opposite end with either of'adjaeent fine-terminals, and to adapt said opposite end "to be raised and lowered relative to a terminal with which it is caused so to register, for the purpose set forth.

9. In combination, a furnacenf-the char-' acter described provided with 'a stack, a set" of air and gas fines foreach nd of the furnace communicating through the furnace with the stack and presenting terminals at a common point, a fine leading to the stack and presenting terminals at said common point, and switching-ducts rotatably mounted at one end on'said gas-flue terminals and one of saidstack-fiue terminals, said ducts being interconnected to cause turning of one to simultaneously swingthe free ends of all into registration,' resectively, wit-h either air-flue terminal, eit er of said passageterminals and the other. stack-fine terminal. for the purpose set forth.

10." In a reversingapparatus ofv a regenei atlve furnace, ad ustable coverson the air flue terminals, a switching duct rotatably mounted at one end on the stack-flue terminal, adapted to register at its opposite end with either air-flue terminal, and a connection between said covers and duct for actnat ing the covers by the movements of the duct, for the purpose set forth.

11. In combination, a furnace of the character described provided with a.stack, a set of air and gas fines forea c l end o flange. enitaliaTfiifiifiiiisns li \vith he tack a n' c l resenting terminals at zfefqi; iolrpoint, a iil'eading to thestack iiiid presenting terminals at said common point, gas-supply passages presenting terminals at said point, switching-ducts rotatably mounted at one end on said gas-flue terminals and one of said stack-flue termi-' nals and ada ted to be turned thereon to swing their ree ends into registrationrespectlvely with either air-flue terminal, either of said passage terminals and the other stack-fluete'rminal', covers hinged on the airflue terminals, and means actuated by a duct in turning in one direction to raise one of said covers, for the purpose set forth.

12; In combination, a furnace of the chai' acter described provided with a stack, a set of air and gas fiues for each end of the fur-v nace communicating through the furnace with the stack and resenting terminals at a common point,- a and presenting terminals at saidcon mon point, gas-supplypipes presenting terminals at said point, switchmg-ducts rotatably mounted at one end onsaid gas-fluetermi-- nals and one of said stack-flue terminals and swim ue leading to the stack' adapted to be turned thereon to swing their 'free ends into registration respectively with either air-flue terminal, either of said passage-terminals and the other stack-flue terminal, covers hinged on the air-flue terminals, means for setting said covers, and means actuated by a duct in turning in one direction to raise one of said covers, for the purpose set forth.

13. Incombination, a furnace of the char-.

acter described provided With a stack, a' set" of air and gas flues foreach end of the fur nace communicating through the furnace with the stack and presenting-terminals ata common point, a flue leading to the stack and presenting terminals at said common point, gas-supply'passages presenting terminals at said point, switching-ducts rotatably mounted at one end on said gas-flue terminals and one of said stack-flue termi- T nals and adapted to be turned thereon. to

the air-flue terminals and provided with" crank-arms, a rodconnected between its ends With the pivotal. end of the duct on said stack-flue terminal and working at its ends,

through said arms, and stops on therod near their free ends mto registration re-' spectively with eitherv air-flue terminal,

its ends for en aging the crank-arms, for

the purpose set orth.

' THOMAS BLAIRQJR.

In presence of- I N, B. DAvIEs,

R. A. SorrAnrER. 

